Kanata Akehoshi, the 15-year-old main protagonist, represents Earth in a solar system-wide athletic tournament set in the year 5100, competing for the title of Cosmic Beauty. She possesses brown hair reaching her chest, pink eyes, stands 1.57 meters tall, and has blood type O.

Hailing from a family of Japanese potato farmers, Kanata developed exceptional physical abilities through childhood agricultural labor. Her grandmother, former Cosmic Beauty Akari Kanzaki, taught her the fundamentals of various sports, earning Kanata's lifelong love and respect. She has a younger sister named Hinata Akehoshi.

Kanata's personality is bright, cheerful, and quick to form friendships. Her defining motivation stems from a childhood promise made to a girl from a crashed escape pod, inspiring her pursuit of the Cosmic Beauty title. After qualifying in the Antarctic preliminaries, she advances to the main tournament.

During the competition, Kanata reunites with Eva Garenstein, the enigmatic representative of the Von Esclavo colony, recognizing her though their prior connection remains undisclosed initially. She interacts with other competitors including Shelley Wong, a Venusian athlete with prosthetic limbs who resents pity, and Lydia Gurtland, the confrontational Martian representative. Kanata approaches these relationships with inherent optimism, often bridging conflicts through mutual understanding.

Her athletic journey emphasizes perseverance and growth, confronting challenges that intertwine personal ambitions with broader political stakes tied to the Cosmic Beauty title. The narrative frames her development around courage, hope, and pride as she competes in events blending traditional Olympic sports with futuristic disciplines.